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About obesity

What are the causes of overweight and obesity?

Losing weight and keeping it off is often seen as a question of “energy in and energy out” – in other words, how much you eat and how much you move. But science has proven that there are many causes of overweight and obesity, some of which are beyond your awareness or control.1,2

3 min. read
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Obesity is a chronic disease. And just like many other chronic diseases, it develops over time from a combination of biological, psychological and environmental factors.1,3

The causes of overweight and obesity are complicated and vary from person to person. These include:1,4

  • Genetics: Tiny genetic variations can make you more likely to carry weight and gain more weight over time.
  • Hormones: The balance of hormones in your body can affect your appetite and food choices, as well as how much energy you use.
  • Stress: High stress levels can make you overeat and gain weight.
  • Sleep: How much and how well you sleep can affect your hormones, which can make you eat more food.
  • Medications: Some medicines can increase your appetite or affect your metabolism so that you gain weight.
  • Environment and socioeconomic status: Where you live and your access to different kinds of food is related to weight gain.

There are many factors that not only lead to weight gain, but can make it difficult to lose the weight and keep it off. Understandably, it can be hard to know the best way forward in treating or managing overweight and obesity.

Much more than in-and-out: Complex reasons for weight gain

Although the causes of overweight and obesity are complex, there are people who think that it's only a matter of lifestyle. It's a common belief that if a person only ate the right food and exercised in the right way, they wouldn't gain weight.2,4

On some level, it is true. Losing weight does depend on the balance between how much energy you have (from the type and amount of food you eat) and how much energy you use (by exercising or carrying out normal body functions like breathing). But, this dramatically simplifies the issue and can be hurtful for people living with overweight or obesity. Eating less and moving more isn't always enough to manage your weight.4

Understanding the causes of overweight and obesity is the first step

By taking an approach to obesity that is similar to other chronic diseases, healthcare professionals can help you transition to a healthier lifestyle.

To manage your weight in the best way, the first step is to identify which causes play a role. Since these vary from person to person, the approach should too. Every individual needs to manage their weight and address their own specific barriers to losing weight in a different way.

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Tools to help you

Essential tools to monitor your health and have productive conversations with a doctor.

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Take the first step and find the doctor for you

Talk to a doctor about treatment options that could help prevent the weight you lose from coming back.

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Talk to a doctor about weight management

Use our helpful guide to prepare for a productive conversation with a doctor about what could be contributing to your weight gain, and to help you create a weight management plan to suit your needs. 

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References
  1. Wright SM & Aronne LJ. Abdom Imaging 2012;37(5):730–732.
  2. Puhl RM & Heuer CA. Am J Public Health 2010;100(6):1019–1028.
  3. Yumuk V, et al. Obes Facts 2015;8(6):402–42.
  4. Hall KD, et al. Am J Public Health 2014;104(7):1169–1175.
  5. Kaplan LM, et al. Obesity (Silver Spring) 2018;26(1):61–69.

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